Examples of engine components for a car include an ignition plug (a spark plug). A nickel alloy has conventionally been used for an electrode of the ignition plug as disclosed in Japanese Patent Laying-Open No. 2014-029002 (PTD 1) and Japanese Patent Laying-Open No. 2013-178220 (PTD 2).
PTDs 1 and 2 disclose the possibility of corrosion of an electrode of an ignition plug by a corrosive liquid produced due to idling stop. PTD 1 discloses an electrode material composed of a nickel alloy of a specific composition in order to retard corrosion.